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1.
The use of environmental integrative indicators to assess seabed disturbance in estuaries and coasts: Application to the Humber Estuary, UK 总被引：3，自引：0，他引：3
The coastal zone is subject to many and varied changes resulting from human activities and natural processes. Existing or emerging agreements and legislation acknowledge the relevance of indicators for monitoring these. In the UK, following a series of recent workshops, potential indicators of nearshore disturbance have been identified and grouped into three broad indices: 'Coastline Morphological Change', 'Resource Use Change' and 'Environmental Quality and its Perception'. The present study developed these indicators further and tested their use by applying them to 18 sections in the Humber Estuary, Eastern England. The results obtained reflect the current knowledge of the state of the Humber environment and show the potential of integrative indicators but indicate that further studies are required to assess the relative importance of the indicators and their value in reflecting the ability of the ecosystems to sustain natural habitats and populations at a good conservation status. 相似文献
2.
Aubry Vanderstraeten Steeve Bonneville Stefania Gili Jeroen de Jong Wendy Debouge Philippe Claeys Nadine Mattielli 《Geostandards and Geoanalytical Research》2020,44(2):307-329
Atmospheric dust is an integral component of the Earth system with major implications for the climate, biosphere and public health. In this context, identifying and quantifying the provenance and the processes generating the various types of dust found in the atmosphere is paramount. Isotopic signatures of Pb, Nd, Sr, Zn, Cu and Fe are commonly used as sensitive geochemical tracers. However, their combined use is limited by the lack of (a) a dedicated chromatographic protocol to separate the six elements of interest for low‐mass samples and (b) specific reference materials for dust. Indeed, our work shows that USGS rock reference materials BHVO‐2, AGV‐2 and G‐2 are not applicable as substitute reference materials for dust. We characterised the isotopic signatures of these six elements in dust reference materials ATD and BCR‐723, representatives of natural and urban environments, respectively. To achieve this, we developed a specific procedure for dust, applicable in the 4–25 mg mass range, to separate the six elements using a multi‐column ion‐exchange chromatographic method and MC‐ICP‐MS measurements. 相似文献
3.
Mauro Celussi Alessandro Paoli Fabrizio Bernardi Aubry Mauro Bastianini Paola Del Negro 《Estuarine, Coastal and Shelf Science》2008
Diel sampling was performed during an early spring survey in the Northern Adriatic Sea at a coastal station off the Po River delta. Samples were taken every 6 h at spring tide maxima and minima in the sub-superficial layer, at the maximum fluorescence depth (∼3 m). Variations in microbial community structure and its processes were assessed by considering heterotrophic bacteria, picocyanobacteria, viruses, exoenzymatic activities, microphytoplankton, nanoplankton and bacterial/cyanobacterial Denaturing Gradient Gel Electrophoresis (DGGE) profiles. A considerable diatom bloom, mostly supported by Skeletonema marinoi was detected. All microbial parameters except viruses, showed a sinusoidal trend with a 12 h period; only picocyanobacteria expressed relative maxima during high tide, showing a phase in opposition to the other parameters. No substantial changes in DGGE band patterns were detected. Even though the results showed bacterial activities to be influenced by the phytoplankton bloom, all microbial parameters' diel trends (except viruses) preferentially followed the tidal fluctuation rather than the light:dark cycle. 相似文献
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Quantifying groundwater–surface water interactions in a proglacial valley,Cordillera Blanca,Peru 
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下载免费PDF全文 Lauren D. Somers Ryan P. Gordon Jeffrey M. McKenzie Laura K. Lautz Oliver Wigmore AnneMarie Glose Robin Glas Caroline Aubry‐Wake Bryan Mark Michel Baraer Thomas Condom 《水文研究》2016,30(17):2915-2929
A myriad of downstream communities and industries rely on streams fed by both groundwater discharge and glacier meltwater draining the Cordillera Blanca, Northern Peruvian Andes, which contains the highest density of glaciers in the tropics. During the dry season, approximately half the discharge in the region's proglacial streams comes from groundwater. However, because of the remote and difficult access to the region, there are few field methods that are effective at the reach scale to identify the spatial distribution of groundwater discharge. An energy balance model, Rhodamine WT dye tracing, and high‐definition kite‐borne imagery were used to determine gross and net groundwater inputs to a 4‐km reach of the Quilcay River in Huascaran National Park, Peru. The HFLUX computer programme ( http://hydrology.syr.edu/hflux.html ) was used to simulate the Quilcay River's energy balance using stream temperature observations, meteorological measurements, and kite‐borne areal photography. Inference from the model indicates 29% of stream discharge at the reach outlet was contributed by groundwater discharge over the study section. Rhodamine WT dye tracing results, coupled with the energy balance, show that approximately 49% of stream water is exchanged (no net gain) with the subsurface as gross gains and losses. The results suggest that gross gains from groundwater are largest in a moraine subreach but because of large gross losses, net gains are larger in the meadow subreaches. These insights into pathways of groundwater–surface water interaction can be applied to improve hydrological modelling in proglacial catchments throughout South America. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
6.
David Besson Olivier Parize Jean-Loup Rubino Jean-Pierre Aguilar Marie-Pierre Aubry Bernard Beaudoin William A. Berggren Georges Clauzon Philippe Crumeyrolle Yann Dexcoté Nicolas Fiet Silvia Iaccarino Gonzalo Jiménez-Moreno Cécile Laporte-Galaa Jacques Michaux Katharina von Salis Jean-Pierre Suc Jean-Yves Reynaud Roland Wernli 《Comptes Rendus Geoscience》2005,337(12):1045-1054
An integrated study combining facies analysis, multiple group biostratigraphy, identification of depositional sequences and mapping has been conducted on the Miocene Molasse Basin of the external Alps (southeastern France). The filling of the basin is described as resulting from a succession of fluvial incisions subsequently filled during marine transgressions. The major incision is dated as Latest Burdigalian and the major transgression as Langhian. This revised interpretation of the Miocene physiographic evolution of the Molasse Basin implies a re-examination of previous stratigraphic correlations within the basin. To cite this article: D. Besson et al., C. R. Geoscience 337 (2005). 相似文献
7.
The CamClay model has been extensively used in numerous research programmes for constitutive modelling in Soil Mechanics during the past quarter of a century. Several derivations of this model are now available and routinely used for numerical simulations in the geomechanical engineering field. However, to the authors' knowledge the thermodynamical basis of this model in its original form has never been established, at least in a modern thermodynamics framework. The thermodynamics principle proposed by Ziegler is very expedient for this purpose as the non-associated flow rule may be considered. This approach is applied to the CamClay model with the Roscoe dilatancy rule. A dissipation function and free energy are specified in terms of kinematic variables (i.e. state and internal variables), and the material response is derived entirely from these functions. 相似文献
8.
Giorgio Socal Francesco Acri Mauro Bastianini Fabrizio Bernardi Aubry Franco Bianchi Daniele Cassin Joan Coppola Amelia De Lazzari Vinko Bandelj Gianpiero Cossarini Cosimo Solidoro 《Marine Ecology》2008,29(4):449-468
This paper reports on the main biogeochemical properties of the Northern Adriatic Sea in the period May 2003–November 2006 within the framework of the European program INTERREG III Italy‐Slovenia. Spatial and temporal distributions of water density, dissolved oxygen, nutrients (nitrogen, phosphorous and silicon) and chlorophyll a are presented. Multivariate methods such as fuzzy k‐means, self‐organising maps and cluster analysis were used to identify the different water masses and to characterise the temporal and spatial variability of the main biogeochemical features present in the area. The results confirm that the Po River outflows and the meteorological forcing factors are the main components triggering the alternation of stratification and mixing of the water column and that strongly affect the trophic state of the basin. In general, oligotrophic conditions dominate, and were more pronounced offshore, but mesotrophy occurred episodically in May 2004 and July 2005, when phytoplankton blooms were observed concomitant with vertical stability of the water column. A marked interannual variability was also observed, supporting the importance of maintaining long‐term observations of the basin. 相似文献
9.
Paola Del Negro Mauro Celussi Erica Crevatin Alessandro Paoli Fabrizio Bernardi Aubry Alessandra Pugnetti 《Marine Ecology》2008,29(3):375-386
The prokaryotic community, both in terms of abundance and activity (exoenzymatic hydrolysis of proteins, polysaccharides and phosphorylated molecules and leucine uptake), was investigated seasonally for a 3‐year period (2004–2006) in the Gulf of Venice (northern Adriatic Sea). By focusing on spatial and temporal variability, the prokaryote dynamics showed significant variations on a horizontal and seasonal scale, but no substantial differences were observed among years. The basin‐scale variability was mainly influenced by allochthonous inputs from the Po river and the Venice Lagoon, which were the main source of nutrients, acting as a ‘bottom up’ control on prokaryotes. On a seasonal scale, all the microbial parameters (except the polysaccharide degradation) showed significant variations following the temperature fluctuations. The annual rate of change was very low for all the chemical, physical and biological parameters and only the abundance and phosphatase activity of the prokaryotes differed significantly among years. 相似文献
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Geoarchaeological analysis of the Middle and Upper Palaeolithic record preserved in cave, rock-shelter and open-air sites in the northern sector of the Meso-Cenozoic of the Western Iberian Peninsula margin (Portugal) reveals several disconformities (erosive unconformities), hiatuses and surface stabilization phases. A recurrent disconformity, dated to ca. 29,500-32,000 cal yr BP, in the time range of Heinrich event 3, must correspond to a main erosive event related to the impacts of climate change on the landscape, including a reduction in vegetation cover and altered precipitation patterns, with the consequent accelerated down-cutting by stream systems, slope reactivation and endokarstic reorganisation, causing the erosion of sediments and soils accumulated in cave, rock-shelter and open-air sites. These processes create a preservation bias that may explain why Early Upper Palaeolithic finds in primary deposition context remains exceptional in the carbonate areas of central-western Portugal, and possibly elsewhere in the other places of Iberia. The impact of such site formation processes must therefore be duly considered in interpretations of the current patchy and scarce archaeological record of the Middle-Upper Palaeolithic transition in south-western Iberia. 相似文献